London, UK. 11th February 2017. As air pollution kills thousands every year, hundreds of cyclists set out from Trafalgar Square to stage a 'Dye-In' protest outside The Treasury demanding that the Chancellor increase funding for cycling, rising to 10% of the UK transport budget by 2020. Credit: Steve Parkins/Alamy Live News

London, UK. 11th February 2017. As air pollution kills thousands every year, hundreds of cyclists set out from Trafalgar Square to stage a 'Dye-In' protest outside The Treasury demanding that the Chancellor increase funding for cycling, rising to 10% of the UK transport budget by 2020. Credit: Steve Parkins/Alamy Live News

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